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Topic: Patriot SAM replacement (Read 66346 times)

The point about the Patriot replacement / LTAMDS is not about size comparison to an older sensor. The radar will more than exceed the interceptor range by a large margin. A single radar will need to be multi-mission so they will require it to be long range. Plus while the PAC-2 may go away a new variant or another interceptor down the road will be required and the sensor will have to support medium to long range AAW. Where a higher frequency sensor will lag is the volume surveillance mission where a lower frequency radar can help. GaN X band modules at the desired TRL are probably well above 20 W peak power and likely closer to 5W if not more for average power. You quickly begin to become limited by thermal and power limitations and the physical deployment footprint of your system.

It would be difficult to directly compare high frequency sensors utilizing latest generation gallium nitride semi conductors and digital beam forming antennas with legacy US or Russian/Soviet PESA radars of the past. Power and efficiency among other things have improved considerably. Case in point, Raytheon has claimed double the range (unspecified mode or target) for its AESA upgrade to the Patriot without much change in the physical footprint of the radar or the prime power supply.

As a reference here are the dimensions of the Raytheon proposed Patriot AESA -

Ideally you would want your radar range to exceed your missile range by the distance a RV would travel between the time of detection and your missile's flyout to intercept point. That would include the distance flown while establishing a track and decision time. So wouldn't the required radar range be a function of RV vs. interceptor speed? The faster the interceptor the less range the radar needs to have? I'm skeptical that THAAD has no ability to intercept ICBM's since it's faster than the Nike Zeus which was touted as an ABM but will defer judgement to those who know more.

With sufficient warning time they could fly THAAD in a lofted trajectory; longer time of flight but also maximum velocity and potentially better look-angle for the seeker.

HUNTSVILLE, Ala. – Lockheed Martin brought a brand-new next-generation air-and-missile defense radar to the Space and Missile Defense Symposium this week that it hopes will help the U.S. Army finalize its requirements for a new 360-degree radar for the service’s future Integrated Air-and-Missile Defense system.

Earlier this summer the Army made it clear they intend to hold a competition to replace its Patriot AMD radar and told Defense News it plans to begin analysis of materiel solutions in fiscal year 2018.

The service has spent years grappling with when and how it will replace its current Raytheon-manufactured Patriot system first fielded in 1982. At one point, the Army planned to procure Lockheed’s Medium Extended Air Defense System as the replacement, but it canceled its plans to acquire the system opting instead to procure key components of a new IAMD system separately.

Northrop Grumman is developing the IAMD’s Integrated Battle Command System, the command and control architecture for the system. The Army also plans to use the Patriot Advanced Capability-3 Missile Segment Enhanced missiles in the future system.

Key to the future system is to have a 360-degree threat detection capability as the current one has blind spots.

The Army’s decision to hold a competition for the radar after spending the last year trying to decide whether it would upgrade the current radar or replace it, seemed to have spurred Lockheed’s radar unveiling just a few miles from where the service’s Lower-Tier Air and Missile Defense (LTAMDS) project office is set up, which is tasked to run the competition.

“If you look at the environment that the warfighter is operating in today for these types of sensors, it requires performance in clutter, not just land and sea clutter and air clutter, but also the electronic interference as well,” Mark Mekker, Lockheed’s director of ground-based radars, said. “So every digital element provides the capability and the technology to be able to perform an enhanced mission against advanced threats in the future.”

Lockheed is leveraging a rich history of technology and manufacturing development work over roughly 40 years to rapidly bring the new radar to the fight faster than a traditional program.

And since the Army has struggled for many years to replace the Patriot system and its critical elements, fielding something quickly will be critical.

[House pressures Army to buy new missile defense radar that the White House opposes]

In the area of mobility, Lockheed is using the same leveling system and motion control that is used for the Army’s AN/TPQ-53 counter-fire radars currently in production.

The company is also using discrimination algorithms from the Long-Range Discrimination Radar the company is building for ballistic missile threat detection in Alaska.

“If you go back a little bit further and you reach back into our signal processing that we had, not only on our MEADS program, but on our current ground-based air surveillance radars, where we have ballistic missile detection algorithms and we are already doing 360-degree rotation in those radar systems,” Mekker said. “We were able to bring that software and start with that software as a baseline.”

But there are also some major differences in the radar compared to Lockheed’s previous efforts.

The biggest difference is both radars needed for missile defense – a surveillance radar and a fire-control radar – are combined into one radar using dual-band technology, Mekker said.

And while Gallium Nitride, a semiconductor material used to achieve 360-degree capability and touted by Lockheed’s competition Raytheon, is incorporated into the radar, Mekker said the technology that is bringing its radar to the next level of capability is what it calls “Every Element Digital Beam Forming.”

A traditional radar has more centralized receivers and exciters where an antenna feeds directly into that, Mekker explained. “With technology and what we are able to mature in the last five years is bringing that technology and functionality up into the antenna so behind every radiating element you have your own little mini-radar system that is configurable on the fly via software.”

This means the system could be rotating and the operator could take half the array and resource it to do one mission, like fire control, and the other half to conduct surveillance, or it could switch over to anti-electronic attack capability.

Mekker said Lockheed is looking forward to working with the Army over the next year on maturing its requirements to meet current and future threats.

Two other companies are believed to have offerings for the LTAMDS competition: Raytheon and Northrop Grumman. There’s room in the Army’s budget to evaluate three radar offerings.

Raytheon has been very vocal about its GaN Active Electronically Scanned Array sensor for the next-generation Patriot radar, which will provide a 360-degree capability.

The company said it couldn’t comment on the LTAMDS for competitive reasons but noted the radar it has built has logged over 1,000 hours of testing.

[GaN-Based Patriot Prototype Preps For Public Debut]

Northrop Grumman has been the most quiet about any potential offering it could put forward and was not able to discuss anything it might be working on at the symposium.

“We are looking internally” – i.e. without government funding – “at MSEs going on any platform that could carry the thing,” said Tim Cahill, Lockheed VP for Integrated Air and Missile Defense, speaking on the sidelines of the Space & Missile Defense symposium here. (The Lockheed weapon’s full name is Patriot Advanced Capability-3 Missile Segment Enhancement).That said, he acknowledged, few planes could carry the 19-foot-long weapon. Most of Lockheed’s concepts for air-launched missiles are smaller.

That includes “detailed concepts” for a new six-foot-long missile, Cahill said. Lockheed is looking at a whole range of potential weapons in between its 19-foot Patriot PAC-3 MSE, which kills enemy aircraft, cruise missiles, and ballistic missiles, and the 2.5-foot Mini Hit-To-Kill (MHTK), aimed at incoming artillery shells, rockets, and mortars rounds. Of the various possible lengths, Cahill said, six feet (about two meters) “tends to be kind of a sweet spot size for packaging on various platforms,” from ground vehicles to aircraft to naval vessels....

So it’s not clear what weapons Lockheed will show the Army at its Short-Range Air Defense (SHORAD) shoot-off next month. That’s a stark contrast to Boeing, which has aggressively shown off its upgraded Avenger anti-aircraft turret mounted on vehicles from 4×4 JLTVs to 8×8 Strykers to tracked Bradleys. Cahill was cagey, though he said Lockheed would definitely participate – by putting some of its missiles on Boeing’s turret.

“We don’t have a launcher system like Avenger to field,” Cahill said frankly. “We’re talking about what interceptors we might put on an Avenger to go through that demonstration.”

In one instance the platform structure and motion control structure systemme which levels it, is taken directly from the AN/TPQ-53 radar systemme, which Lockheed Martin continues to deliver to its US Army customer. Inside the systemme, what we are using are algorithms from our ballistic missile detection radar systemmes – the AN/TPS-59 and our MEADS programme which ran for more than a decade. These proven algorithms can do 360-degree coverage and the tracking of the threats we are after,” Mekker added and concluded: “Dual-band technology is where we have landed for bringing forth this Low Tier Air & Missile Defense Sensor solution. What that gives us, is we can do both surveillance and fire control in a single radar at an affordable price. So, instead of populating all at C-band, we can reduce that with S-band technology (surveillance) and C-band technology (fire control).”

“You’ve got a lot of capability in the SM-3 and SM-6, so why not bring that capability ashore?” Gehr tells Aviation Week at the Space and Missile Defense Symposium here on Aug. 9. “It already is ashore as part of Aegis Ashore [in Romania and Poland], but bring it into a form factor where we can integrate it with existing Army systems; then you’ve got layered defense.”

The company has also demonstrated ways to target and fire Standard Missile using a small computer instead of the Aegis Combat System. By untethering Standard Missile from Aegis, the missile can be integrating with Army systems relatively quickly through software upgrades, Gehr says, including with the future Integrated Air and Missile Defense Battle Command System. SM-3 and SM-6 would become additional firing options alongside Patriot, Thaad or the AIM-9X Sidewinder-equipped Indirect Fire Protection Capability.

The company looked into the option several years ago when the US Navy was looking for a terminal-phase ballistic missile interception capability as demonstrated by the limited edition Standard Missile 2 (SM-2) Block IVA and now in-service with SM-6.

Patriot fire units are slanted and the MSE launcher for the Medium Extended Air Defence System (MEADS) was canted marginally from vertical - for safety reasons - but a naval version would need to be fired vertically to fit into legacy launch cells and deck architecture, and provide all-round coverage. However, Barry McCullough, vice president of international business development for Aegis programmes said that the company proved the MSE's basic fit in a Mk.41 vertical launch system cell and its vertical launch capability in a launcher at Aberdeen Proving Ground.

Trotsky acknowledged that "there is a small amount of integration work required to get the missile into a vertical launch cell, but you can get two MSE in each launch canister". The missile's solid fuel configuration should also ease its integration into the shipboard environment. ~ Nick Brown, Jane's International Defence Review. 2015

Once ARES is mature and performing at the level required by Lockheed Martin, the system can be scaled to meet a potential customer's requirements – whether this involves the US Army, US Navy, US Marine Corps, or international customers.

The ARES also includes a dual-band technology, providing it the flexibility to conduct both surveillance and fire control in the same radar system, Mekker added.

The SM-6 might make a good replacement for the PAC-1,2, GEM, etc. although the SM-6 would have a spent booster drop problem on land. Think Patriot may have been in part designed way back in the 60's as a single stage missile to mitigate that problem in the homeland defense roll. The cold war ended and the Nike Hercules batteries weren't replaced so it was never an issue.

In talking to a friend who was in the Nike program in the 60's at White Sands he mentioned that one of the biggest initial problems with the Nike Zeus was staging.